The invention pertains to a composition for use in diagnosing the transport function of the fallopian tube and to a method for preparing said composition.
The inability of a fallopian tube to transport an ovum, i.e. a blastocyst from the ovarian region into the lumen of uterus, is the frequent reason for female infertility and is estimated to be the cause for one third of all infertile marriages. The reason may be anatomic, e.g., a totally impervious fallopian tube or functional, as when the tube is permeable but the transport does not occur. The latter condition is referred to as functional tubal sterility (FTS) and is usually classified among the so called idiopathic sterilities, the frequency of which is estimated to be 15% of all female infertility. The reason for the disfunction may be various: an inborn hypoplasia, a disorder of muscular activity or a disorder of ovum pick-up. The most frequent reason, however, is the persistent spasm of the isthmic sphincter, which narrows the lumen of this section to 150 um, substantially smaller than the size of the blastocyst which has a diameter of 380 to 400 um.
While a surgical treatment is indicated for anatomic defects, the transport disorders are reparable by conservative procedures. A reliable diagnostic method capable of differentiating between the anatomical and functional source of the problem is therefore needed.
The recent diagnostic procedures employ the ascendent or descendent methods. In the ascendent methods, the fallopian tube is filled by application of a liquid or gas (CO.sub.2) into the uterotubal tract. By use of laparoscopy, the penetration of a suitably colored liquid is observed and/or a resistance against the introduced medium is recorded. There has also been described a method utilizing the active transport of radioactive microspheres from human albumin (diam. 10-35 um; labelled with .sup.99 Tc; S.C. Stone et al., Fertil. Steril. 43, 757 (1985)), which were introduced into the vaginal fornix and to the inlet of cervical channel. Hysterosalpingographs were recorded during 60 minutes by means of scintigraphy. The disadvantages of such a procedure consists in the possibility that penetration of the applied medium through a region of spasm (which prevents the transport of the blasocyst) will occur and a false-positive result will be obtained. A detection of a change in pressure (resistance) usually will indicate a spasm during the application under pressure (cineinsufflation), but the spasm may actually have been induced as a consequence of irritation as a result of the procedure, in which case and the result may be a false-negative.
In the descendent methods, a diagnostic medium of particular character is applied into the region of ovaries or into Douglas' space and its penetration into the lumen of the uterus is followed. Chinese ink (D. v. Ott, 1925; Ztbl. Gynekol. Nr. 10,546), starch grains (A. Decker and M. Decker, 1954; Obstct. Gynecol. 4, 35), or colloidal radioactive gold (.sup.198 Au) (A. Stabile and F. E. Leborgne, 1958; Int. J. Fertil. 3, 139) are used for this purpose. In the experiments with animals (rabbit), also models of ovum were used in the form of spherical particles of crosslinked dextran (Sephadex) (H. B. Croxatto, C. Vogel, J. Vasquez; J. Reprod. Fert. 33, 337 (1973)) or polystyrene (M. J. K. Harper et al., 1960; J. Reprod. Fert. 1, 249), which can be labelled with radioactive iodine 125I (C. J. Pauerstein and B. J. Hodgson, 1976; Am. J. Obstet. Gynecol. 124, 840).
The aforementioned methods are disadvantageous in clinical application because the particles (Chinese ink, colloidal gold, starch grains) are too small so that they pass through the isthmic region even in the case of persistent spasm. The models of ovum used in the experiments with animals differ in physical properties and surface characteristics from the naturally transported objects on the one hand, and are objected to from the standpoint of patient safety (esp. polystyrene), on the other.